הָב֥וּ לָכֶ֛ם שְׁלֹשָׁ֥ה אֲנָשִׁ֖ים לַשָּׁ֑בֶט וְאֶשְׁלָחֵ֗ם וְיָקֻ֜מוּ וְיִֽתְהַלְּכ֥וּ בָאָ֛רֶץ וְיִכְתְּב֥וּ אוֹתָ֛הּ לְפִ֥י נַחֲלָתָ֖ם וְיָבֹ֥אוּ אֵלָֽי׃
Appoint three representatives from each tribe; I will send them out to go through the country and write down a description of it for purposes of apportionment, and then come back to me.
(The above rendering comes from the RJPS translation, an adaptation of the NJPS translation. Before accounting for this rendering, I will analyze the plain sense of the Hebrew term containing אִישׁ — or in this case, its plural אֲנָשִׁים.)
In the clause הָב֥וּ לָכֶ֛ם שְׁלֹשָׁ֥ה אֲנָשִׁ֖ים לַשָּׁ֑בֶט, the referents’ gender goes without saying (it is implied by the condition of tribal representation, and by a cultural association of land surveying/assessment with male expertise). The label אֲנָשִׁים profiles its referents as essential participants in the newly depicted situation. (This noun is standard for sketching the defining participants in the desired situation that a speaker’s directive wishes to achieve.) The situation is one of agency, in which the prepositional ל indicates the representation of one party by another party (see Baruch Levine, Numbers [Anchor Bible commentary], at 1:15; 13:4). Thus the literal meaning of the phrase is akin to “three participants representing each tribe.”
Similarly, in the co-references to these same participants in vv. 8 and 9, הָאֲנָשִׁים is used as the standard label for the respective purposes of efficiently introducing and then re-situating an essential (and identifiable) participant, as the depicted situation develops.
As for rendering into English, the NJPS ‘Appoint three men from each tribe’ is liable to be misconstrued, as if the point of the designation were to specify that the desired candidates be adult males. The new rendering is the more idiomatic English way to express the idea of representation. The referents’ gender is readily inferable from the situational context.